This study focuses on an error correction technique, known as the recast. Recasts have been categorized as implicit negative evidence (Long & Robinson, 1998). Although studies on corrective feedback show that teachers use a variety of corrective feedback techniques, of which the recast is the most frequent, the effectiveness of the recast in triggering immediate uptake (Lyster & Ranta, 1997) or attention (Roberts, 1995) has been questioned. In contrast, other studies show a positive effect for recasts (Iwashita, 2003). The ambiguous results suggests that new typology of recasts is warranted (Sheen, 2004).
Motivated by cognitive aspect of language acquisition, hypothesis has been advanced that one crucial factor to determine the effectiveness of recasts is perceptual saliency?the recast that is perceptually salient may impact differently from that is not perceptually salient (Sheen, in press). Adding perceptual saliency in the form of stressed intonation can add power to recasts, making them explicit enough to trigger noticing and perception, and to stimulate reformulation of errors, but not too explicit to interfere with communication.
Approximately 50 low-intermediate learners of Japanese engage in picture description tasks and receive different types of corrective feedback (salient recasts, nonsalient recasts, and negotiation moves) from a native speaker. The NS/NNS interactions are analyzed in terms of learners?f noticing, perception, and detection of their own errors, and the quality of utterances that follow each corrective move via transcribed data from the picture description tasks and comments from the stimulated recall sessions.
The findings paint a fine-grained picture of differential effects of each corrective moves. This study suggests that adding the element of perceptual saliency and enhancing the positive evidence to the construct of recasts is more beneficial than nonsalient recasts or negotiation moves. Taking perceptual saliency into consideration increases our understanding of how recasts function to promote L2 acquisition.